Process for producing corosolic acid

• US 20050020681A1
• Filed: 06/15/2004
• Published: 01/27/2005
• Est. Priority Date: 06/16/2003
• Status: Active Grant

• Current Assignee: Ticona LLC (Celanese Corporation), TOKIWA Phytochemical Co., Ltd.
• Original Assignee: TOKIWA Phytochemical Co., Ltd.
• Inventors: Kitajima, Mariko, Ishizuka, Tomoko, Takayama, Hiromitsu, Seo, Shujiro
• Granted Patent: US 7,071,229 B2
• Time in Patent Office: Days
• US Class Current: 514/559
• CPC Class Codes: A23L 33/105 Plant extracts, their artificial duplicates or their derivatives
• CPC Class Codes: A61P 3/10 for hyperglycaemia, e.g. antidiabetics
• CPC Class Codes: C07J 63/008 Expansion of ring D by one atom, e.g. D homo steroids

Abstract

This invention provides an improved process for producing corosolic acid starts from ursolic acid, which occurs in plants in relatively large amounts, the method comprising the steps of oxidizing the hydroxyl group at 3-position and utilizing the carbonyl group at 3-position to introduce a hydroxyl group stereospecifically into the 3-oxoursolic acid at the 2α-position adjacent to the hydroxyl group at 3-position.

Claims

1. A process for producing corosolic acid or a corosolic acid ester, which comprises the steps of:

a) oxidizing a compound of formula III;

[where R¹ is a hydrogen atom or a C₁-C₆ alkyl] to a compound of formula IV;

[where R¹ is a hydrogen atom or a C₁-C₆ alkyl]; and

b) reducing the compound of formula IV to corosolic acid of formula I;

[where R¹ is a hydrogen atom or a C₁-C₆ alkyl] or a corosolic acid ester.

2. The process according to claim 1, wherein the step of oxidizing a compound of formula II:

3. The process according to claim 1 or 2, wherein R¹ is a hydrogen atom.

4. The process according to claim 1 or 2, wherein R¹ is a C₁-C₆ alkyl and which further includes step d) of hydrolyzing the compound of formula I:

5. A pharmaceutical composition comprising corosolic acid or a corosolic acid ester that are produced by the process according claim 1, and which is to be used for preventing or treating diabetes mellitus or for controlling blood glucose level.

6. Food and beverage that comprise corosolic acid or a corosolic acid ester that are produced by the process according claim 1.